Smoke consumer and fuel economizer



June 20, 1933.-

N. BEDARD 1914 4-76 SMOKE CONSUMER AND FUEL EGONOMIZER Filed May 22,1931 2 Sheets-Sheet 1 wmmtoz June 20, 1933. N. BEDARD SMOKE CONSUMER ANDFUEL ECONOMIZER Filed May 22, 1951 2 Sheets-Sheet 2 FIE-T. 4-

Patented June 20, 1933 UNITED STATES NAPOLEON BEDARD, F QUEBEC, QUEBEC,CANADA SMOKE CONSUMER AND FUEL ECLONOMIZER Application filed May 22,1931, Serial No. 539,362, and in Canada December 10, 1 931.

The invention aims to provide a new and improved device in the nature ofa secondary fire-box for thoroughly mixing a1r with products ofcombustion discharged from a 5 primary fire-box and completely burningall unburned fuel units which would otherwise escape, thereby preventingdense smoke and obtaining greater efficiency from the fuel.

With the foregoing in view, the invent on resides in the novel subjectmatter hereinafter described and claimed, description being accomplishedby reference to the accompanying drawings. I

Fig. 1 is a vertical longitudmal sectional view partly in elevationshowing the mvention embodied in the bridge wall of a bo1ler furnace.

Fig. 2 is a horizontal sectional view on llne 2-2 of Fig. 1.

29 Fig. 3 is a transverse sectional view partly in elevationsubstantially on line 33 of Fig. 1.

Fig. 4 is an enlarged horizontal sectlonal view through one of thesecondary fire-boxes.

Fig. 5 is a vertical transverse sectional view on line 55 of Fig. 4.

The general construction shown by the above-described drawings, hasproven to be efficient to the maximum, and hence, maybe 30 considered aspreferred. This constructlon will be rather specifically described, w ththe understanding however, that with n the scope of the invention asclaimed, variatlons may be made.

The invention is shown in connection with a return tube boiler B but isnot restricted to use with such a boiler. Under the boiler 13, a bridgewall WV has been shown which, with the exception of the conducting meansafforded by the two secondary fire-boxes S, en-

tirely segregates the fire-box F from the rear combustion chamber C,said secondary fireboxes being built in the bridge wall W and havingtheir inlet ends I in direct communlcation with the fire-box F whiletheir CllS- charge ends D communicate with the chamber G through theinstrumentality of a recess R formed in the rear portion of said bridgewall W. Both of the secondary fireboxes S are of the same constructionand hence a description of one will suflice for both. The secondaryfire-box S is in the form of a conduit of any appropriate fire-resistingmaterial, and while said conduit is shown of cylindrical cross section,it may be of any other desired formation. The inlet end I of'the'conduit is provided between its inner and outer sides with an airmanifold 6 having an air inlet 7 which communicates with piping 8leading from a blower 9, said blower preferably having a shutter or thelike 10 either manually or automatically controlled,

for regulating the amount of air handled by the blower, as may berequired. Air-injecting means provided by openings 11, communi- 165 catewith the manifold 6 and with the interior of the conduit. These openingsare at acute angles to the longitudinal center of the conduit as seen inFig. 4: and are at acute angles to radii of said conduit as illustrated5710 in Fig. 5, the openings being so positioned that they direct jetsof air inwardly toward the center of the conduit and toward the deliveryend D of the latter, and serve to violently whirl this air. The air issupplied through the piping 8 at such pressure that the velocity of thejets discharging from the openings 11 is greater than the velocity atwhichthe products of combustion reach the conduit or secondary fire-box.Thus, the gases and the unburned fuel units therein,

- are accelerated and are so agitated that good initial mixture of airwith the combustion products takes place.

Between its inlet and discharge ends I and I) respectively, thesecondary fire box or conduit S is provided with an abrupt angle 12, thedischarge end D being thus directed laterally from the major portion ofsaid secondary fire-box or conduit. Hence, the 190 portion 13 istransverse to the path along which the unburned fuel units and the airand gases, initially travel. This portion 13 therefore constitutes abattle in the path of the initially mixed air and combustion products,said bafiie being adapted to abruptly change the direction of and tothereby agitate and thoroughly mix the air, the unburned fuel units andthe gases, producing such a homogeneous mixture that complete 1combustion will take place. The flame from such combustion is blown fromthe force of the incoming air, through the recess R and into the rearcombustion chamber 0, some of 5 said flame finding its way through theboiler tubes. The complete combustion of fuel units which wouldotherwise escape, adds materially to the efficiency obtained from thefuel and also insures that no dense smoke shall escape from the furnace.

The gases and unburned fuel units reach the secondary fire-boxes S at avelocity of from ten to fifteen feet per second. The air from the blower9 is discharged through the airinjecting openings 11 at a speed rangingfrom thirty to forty feet per second. The unburned fuel units thusacquire a speed ranging from twenty-five to thirty feet per second.These unburned units possess a density approximately three-hundred timesgreater than the density of the gas escaping from the fire-box, and theyhave a tendency to travel straight ahead and hence they impinge withgreat force upon the bafile 13. An

-abrupt change in the direction of the air, gases and unburned unitswhich have been initially mixed under the influence of the air jetsinjected through the openings 11, is thus effected, with consequentagitation which inaosures such a thorough mixture that completecombustion takes place.

As excellent results are obtainable from the details disclosed, they arepreferably followed, but attention is again invited to the as fact thatwithin the scope of the invention as claimed, variations may be made.

' In combination, a boiler, a bridge wall extending downwardly from saidboiler and 40 having a rearwardlyn opening recess in its upper portion,a fire-box in front of said bridge wall, two conduits formed in saidbridge wall with their front ends communicating with said fire-box, saidconduits having their rear ends turned laterally inward intocommunication with said recess, the front portions of said conduitsbeing provided with air-injecting openings directed obliquely rearward,and means for supplying air under pressure to said openings.

In testimony whereof I affix my signature.

NAPOLEON BEDARD.

